Readers asked, Valerie Blaine answers

A Canada goose flaps its wings after bathing in the Fox River near Boy Scout Island in St. Charles. Some readers wonder what the best way is to control goose overpopulation in the suburbs.Laura Stoecker | Staff Photographer

Candied yams, or sweet potatoes, can be a wonderful treat on Thanksgiving, but they come from a different plant than the yam that grows in the wild.RICK WEST | Staff Photographer

Cougars, mountain lions and panthers are different names for the same cat.Courtesy of Eastern Cougar Network

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There's no such thing as a dumb question, though. Some are thought-provoking and lead to some engaging discussions. These become stories that are fun to tell.

A tale of two yams

One such question came up at Thanksgiving when I was chatting with some locavores (folks who advocate eating locally grown food).

"Are there any locally grown yams?" one of the foodies asked. Well, yes and no, I said.

The native plant known as wild yam grows in several preserves in Kane County. It's not the same as the vegetables called yams in grocery stores. Two different species, two different plant families, two different continents.

The yam commonly sold in the store is really a sweet potato, or Ipomaea batatas. It hails from Central America and is one of the most important staples for many cultures in tropical regions. It was introduced to Europe after Christopher Columbus' first visit to the New World, and like many items, it made its way back across the Atlantic from Europe to North America.

The sweet potato belongs to the morning glory family, the Convolvulaceae -- a plant family notorious for entheogenic, or psychoactive, properties used in shamanic rituals.

"Our" yam, on the other hand, is in the family Dioscoreaceae. The species that grows in Kane County, Dioscorea villosa, is a twining, climbing vine with lovely leaves and small, inconspicuous flowers in summer. While some of its close relatives produce edible tubers (roots), D. villosa is decidedly NOT edible. As the Missouri Botanical Garden website warns, D. villosa is "a virtual cornucopia of organic compounds of medical interests."

A common name for this plant is colic root, referring to its one of its many medical applications. It has also been used as a pain reliever for menstrual cramps and childbirth. Diosgenin, one of its primary chemical constituents, has been tested as an anti-inflammatory.

Suffice it to say that the native yam is a cool plant with interesting homeopathic uses. As our conversation about local food sources concluded, we all decided to steer clear of it in the kitchen.

Those pesky geese

Another question came last week in a coffee shop when a woman asked me what the forest preserve district could do about those pesky geese. You know, the big noisy "Canadian" ones.

First, I joked, let's not blame Canada. Technically, the name of the bird is Canada -- not Canadian -- goose. There are seven subspecies of the Canada goose. The most common subspecies in our area is known as the giant Canada goose.

During migration, the "giant" mingles with numerous other subspecies in marshes and waterways. Many "giants" migrate south with other subspecies in the fall. With mild winters and open water, though, they are not compelled to leave. Many more remain all winter than used to. That means that come summer, thousands of giant Canada geese honk raucous choruses of "Ready! Set! Go!" at breeding time.

The Canada goose problem isn't necessarily one of numbers. It's the mess they leave, and where they leave it. Canada geese are grazers, and they find turf grass quite to their liking. Short, cropped grass affords them food as well as a good lookout for predators (of which there are few on lawns). Unperturbed, the geese eat and eat and eat -- and then, well, they excrete. In vernacular terms, goose poop is gross. It gets all over the grass, the sidewalks, and trails. It can ruin an outdoor wedding, Frisbee games, and family picnics. Strolling about is not "just a walk in the park" anymore. What to do?

A while back, there was a brilliant idea: use biological control. The biological agent of choice was the mute swan. Mute swans are aggressive toward geese so, as the theory goes, they will shoo Canada geese away. The big, graceful white swans were widely introduced for this purpose.

Unfortunately, this purported solution created its own problem. Mute swans are aggressive toward all species, not just geese. (They're nasty toward people, too!) These nonnative, aggressive birds are, basically, bullies from out-of-town. They prevent many species of waterfowl from nesting. They have become a huge problem, particularly in large wetlands and estuaries like Chesapeake Bay.

Mute swans are now a regulated invasive species. So much for that solution.

An effective, win-win solution to the Canada goose problem is to restore native vegetation. In forest preserves, natural areas management involves planting taller, native vegetation as opposed to turf grass. This keeps geese on their toes. They have to be vigilant for predators lurking in the brush. In general, a healthy habitat with native plants and native predators affords checks and balances for Canada geese and a host of other species.

Cougars in Illinois?

There are lots of questions about cats. As in really, really big cats. The Illinois Department of Natural Resources has confirmed four cougar sightings in Illinois this fall. These have been in Jo Daviess County, Morgan County, Pike County, and Calhoun County. And of course, there was the famous cougar appearance in the northern suburbs in 2008. This has certainly caught people's attention.

What are the chances of a cougar showing up in Kane County?

"Hard to say," said Forest Preserve District wildlife biologist Bill Graser. Bill and I chatted about the likelihood of such large predators here, with such small, fragmented habitat, but based on what's shown up on trail-cams, it seems just about anything's possible.

And finally, there's a question that always comes up in the cougar discussion: "What's the difference between a cougar and a panther?" Answer: no difference. Felix concolor is a cat with many monikers: mountain lion, cougar, panther, catamount. Whatever you call it, keep a good distance -- and remember to take a picture!

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